NEW YORK (TheStreet) -- How do you invest if you believe man-made global warming is about to decimate the planet? And how do you invest if you think that's a lot of hooey?Most would say those who deny global warming should first bet on coal, oil and gas, but that's no way to make money. If you think your thesis is right, you bet on stocks that go against the other way of thinking. So if you accept the scientific consensus that glaciers are melting, temperatures are warming and we're heading over the environmental cliff, you look to sectors that can deal with that reality. Thus, those who think we can keep pumping methane and CO2 into the air without consequence would be wise to buy insurance stocks, especially those that insure against natural disasters. Companies like American International Group ( AIG) and Chubb ( CB) have to be putting more disasters into their models -- it wouldn't be prudent otherwise. If disasters don't occur, these companies are going to be rolling in cash. Best of all, they're both bargains. AIG still sells at slightly less than 12 times its most recent earnings, Chubb at a little more than 12 times. Retailers with global reach should have steady profits if global warming isn't real. So try some Wal-Mart ( WMT), even Target ( TGT), which should see both growth and international expansion. If you don't think Florida is doomed by climate change, maybe you should consider homebuilders. Lennar ( LEN) is a homebuilder based in Miami, which will be completely under water if global warming proceeds as expected. You may also think that in this case there will be lots of extra money around, so how about a gambling stock like Las Vegas Sands ( LVSC) -- Macau is right on the seacoast so it should be fine, right? Scientists think airliners contribute as much as one-fifth of the Arctic's global warming, so no cool planet portfolio should be without companies like Delta ( DAL) that fly over it every day. On the other hand, what if you accept the reality of global warming? How do you invest then?
Conventional wisdom says you buy solar stocks like First Solar ( FSLR), but if warming is happening anyway, how does betting on an outfit fighting it help you? It doesn't. So while it may seem counter-intuitive, how about a farm technology stock like Monsanto ( MON)? The only way to feed people in a warming world is for plants to adapt quickly to that change, and Monsanto's genetically-engineered seeds do that. That's why they already control most of the U.S. corn seed market. Some may try to point you toward water utilities such as American Water Works ( AWK), but as a student of Atlanta history I know an outfit that has done a lot more for water purification, and made a lot more money from it. Coca-Cola ( KO) got into water treatment almost a century ago, to assure the uniformity of the product. No Coke? Pepsi ( PEP). An even better bet in this sector would be Coca-Cola Enterprises ( CCE), which owns many of the company's bottling operations. If demand for potable water explodes and they can skip the sugar syrup, they can do very well, indeed. They've already outperformed Coca-Cola itself over the last decade. While industrial equipment runs on fossil fuels, you need it to deal with huge storms, like Superstorm Sandy, resulting from a warming planet. How about some Caterpillar ( CAT) -- it's down 15% from its high for the year, so it should be a winner. Terex ( TEX) and Joy Global ( JOYG) should also do well, digging out from under disasters. As we saw with Sandy, building supplies of all kinds respond to sudden increases in demand stemming from disasters. Thus get yourself some Home Depot ( HD) or maybe some Lowe's ( LOW). Personally I'm in the middle on all this. I expect warming, but I also expect mitigation to limit the damage, at a profit. That's why my personal portfolio has such companies in it as IBM ( IBM), General Electric ( GE) and Google ( GOOG), because it's innovation that will be at a premium once we finally get serious about dealing with this problem. As I believe we will, all joking aside. At the time of publication, Blankenhorn owned 20 shares of GOOG, 118 shares of IBM, 157 shares of KO, 200 shares of AIG and 316 shares of GE. Follow @danafblankenhor This article is commentary by an independent contributor, separate from TheStreet's regular news coverage.